Nonstoichiometric hydroxyapatite granules for orthopaedic applications

Area of Science:

• Biomaterials Science
• Orthopedic Surgery
• Materials Engineering

Background:

• Nonstoichiometric hydroxyapatite (HA) is a key biomaterial for bone regeneration.
• Developing HA granules with tailored porosity and mechanical properties is crucial for orthopedic applications.
• Existing HA granules may not fully replicate the structural and mechanical characteristics of natural bone.

Purpose of the Study:

• To develop a new method for preparing dense and porous nonstoichiometric hydroxyapatite (HA) granules.
• To characterize the porosity, pore structure, and compression strength of the prepared HA granules.
• To evaluate the clinical efficacy of these HA granules in orthopedic surgery.

Main Methods:

• Preparation of nonstoichiometric hydroxyapatite (HA) granules with controlled "dense" and porous structures.
• Characterization of granule porosity (micro- and macropores) and compression strength (up to 48 MPa for dense, 25 MPa for porous).
• Clinical application of HA granules in 42 orthopedic surgeries on the locomotor system.

Main Results:

• Successfully developed dense HA granules (porosity ≤32%, micropores) with high compression strength (up to 48 MPa).
• Developed porous HA granules (porosity ≤70%) with interconnected micro- and macropores, mimicking spongy bone structure.
• Achieved high clinical success rates in 42 orthopedic procedures, with follow-up up to four years.

Conclusions:

• The new method yields high-quality dense and porous HA granules suitable for orthopedic applications.
• The tailored properties of these HA granules, including bone-like porosity and mechanical strength, ensure their effectiveness.
• Clinical outcomes confirm the reliability and quality of HA granules in treating locomotor system injuries.